Mechanical connections



Sept- 15, 1959 KRAUss ET Al. 2,904,288

MECHANICAL CONNECTIONS Filed Sept. ,5, 1958 another suitable turningtool. device is used for connecting a'portable typewriter ywith thebottom element of its case, the turning of pinneces- Jvatent Y 2,904,288Patented Sept. 15, 1959 "hice MECHANICAL CONNECTIONS :Otto Krauss andHermann Waldenburger, Numberg, Ger- 'many,fassignors to Firma Triumph'Werke Nuernberg AUG., Nurnberg, Germany Application September 3, 1958,Serial No. 758,347 lClaims priority, application Germany MarchfS, 1'958`1S Claims. (Cl. 248-25) The present invention relates to mechanical'connections in general, and more particularlylto amechanical"connection of the type in which -a resilient member is capable ofconnecting two structural elements when Vin deformed position whilepermitting disconnection orsep- 4aration ofthe structural elements whenitis allowed to -reassume -its normal unstressed shape.

-material yin `connecting 'devices between the base of a portabletypewriter case and thetypewriter frame. The cylinder is mounted on apin which is rotatably received in the'base and carries a cam platecausing compression of the .cylinder when the pin is turned. Thetypewriter frameisformed with an opening which receives lthevcylinderbefore the `latter is compressed. By rotating the pinin such mannerasto-cause-compression of-the cylinder, the latter-is deformed yanddefines 'a bulge which bears against the typewriter frame andthusconnects the typewriter with the base or Ybottom element of .itscase Thedisadvantage-of suchconnecting devices isfin that the pin requires animplement "forrotating same `or.it must be formed with a slot to'receiveya screwdriver or In addition, ywhen such a sarily must be eifectedatthe underside of the .bottom element. Thus, the machinezmust be invertedtogether with the bottom element which. is rather. inconvenient andtiresome. It is well known that the connections between a typewritercase and theiportable'typewritershould be operable from within the casefor the express purpose that the llifting of typewriter'and vits lcasemayrbe avoided.

Still further, the cam plate utilized insuch known connecting devicesmust be :soinstalled .that itcannotlrotate with respect to the resilientcylinder. Consequently, .the cylinder must be held under constanttension and is at least slightly Adeformed even when-inidleornon-retaining position. This brings .about certain complications inthe assembling of components parts in such connecting devices.

An important object of thepresentinvention is'to provide Ia mechanicalconnection which overcomes the drawbacks of just describedpriorassemblies in that it is operable from that side of onestructural'element which is turned toward the other structural element to be con--vnected thereto.

vstressed 1state in another position.

ber isunstressed when in idle or non-retaining position.

A further object of the invention/is to provide'a mechanical connectionwhich is particularly suitable l"forreleasably connecting atypewriter-.or another `.oilce machine'with a desk ortwith the bottomelemento'f aportable case,'at least one component partof which may beformed as an integral element of the desk or thelbottom element.

A still 'further object-of the -in-vention is to-providefa mechanicalconnection which is lvery simple, easy i'to operate, easy to install,Vreliable in use, which requires -little space, and-which is capablevoff diversied uses-whenever a connection between twoeor 4morestructurabelements must be established. The :above and certainotherlobject-s of the lVinvention are attained by the provision-f a camassembly whih'is preferably integral with .oneI of 'thetobe-connectedstructural elements,-of a supporting lmember or lbolt forVa resilient retaining member of cylindrical shape, of Ameans forretaining the resilient member von the'bolt, and'oii an actuating devicemounted-'on'the bolt in suchv'manner as lto compresstheresilient'memberin one positionand to permit -return of resilient-member into-originl 'un- The actuating device, when movedvwith respectto`-the-bolt,;is`guidedibe- 'tween and into its 'two positions by`theaforementionetl cam assembly and may perform either radial orangular movements with respect to the'bolt, depending uponftheconfiguration of the cam assembly. Theboltandfthe resilient memben'thelatter `inunstressed. condition, 'are insertable-into an aperture inthesecondstructural'ele- Vment and the resilient'member7 either bymerefriction or by deformation, retains the second'structural .element insuch'position whenthe actuating device is vmovedjn "a direction todeform or at least to'subject the -resilient Vmember to considerablestresses sufficient to preventiremoval l of said resilient member fromthe aperture in the secondstructural element. Thebolt'need not'beturnedwhen the improved mechanical connection Ais actuated either'to connector to disconnect two structural elements and-the actuating device beingtixed'to theibolt atthat side of one structural element which faces theother 'structural element, the connectionmay be operated .from insideand requires no turningof structural elements.

v-When notin retaining position, the resilient member'i's `freelyslidable along the supporting bolt andthuscneefd notbesubjected to anystresses; this. is ofl advantage when the improved mechanicalconnection'is assembled. As

before stated, the cam assembly, preferably-comprisinga pair'of stopsand suit-able sloping orcurved cam` surfaces,

:may be integral with onestructural element, ef.g.' with` the bottomelementI or base of a portable typewriter case, and

the actuating deviceror'lever is then formed withia'ffol- 'lower'portion which `cooperates with the inclined L'cam surfaces .to 1 travel4in. directions toward andiawayJfromtthe ladjacent* end face'oftherresilient memberfandtozthereby either .compress 1 andeventuallyYdeform the latter, tor vtoperrnit return of theresilient memberbackfintofnormal releasing or unstressed shape. .Byformin'gtheamassemblyrasan'integral part of one .structuralelemen eg. of the bottom`elernentin the case/,foraportable typewriter, .the cam assembly may .bemanufacturedby injection molding orby .another suitable processytogether Withthe bottom element. iThus, the costs'formanufacture,'nishing and installation of separatecam assemblies aredispensed with.

The novel features whicharey considered as characteristic for theinvention-are setforth in particular in the appended claims.'The'invention itself, Lhowever,"bo'th as to its construction and itsmethod of operation, together with kadditional objects andadvantagesthereof,will be best zunderstoodf fromihe .followingdescription of Eafspecific embodiment when read in connection with theaccompanying drawing, in which:

Fig. 1 is sectional view of the mechanical connection applied totheVbase forming the bottom elementof a .portable typewritercase, and of astructural element .forming part of the typewriter and placed intoposition for locking to the base; and Y Y Fig. 2 is perspective view ofthe assemblyshown in -Fig. 1, with the structural element lifted abovethe connection.

Referring now in greater detail to the drawing, the base plateor bottomelement 1 of a typewriter case (cover AYnot shown) is integrally formedwith a preferably cir- ,cular projection or protuberance 2 which latter,in turn, Ais integral with a pair of annularly arranged cams each,comprising an undulated substantially semicircular cam surface 4sloping with respect to base plate 1, and a stop Vorlabutmenrt 3.Abutments 3 are diametrically opposed toreach other, i.e. their angulardistance is about 180 degrees, The base 1 and the protuberance 2 definea Vbore, 5^-for reception of supporting member or bolt 6 which may, butneed not, be iixed to the base. The bolt jswingably supports anactuating device or lever 7 whose Aone end*8 constitutes the handgrip oractuating portion and whose other end 9 constitutes a follower pivotablymounted on bolt 6 and adjacent to the sloping cam sur- `faces 4. Acylindrical sleeve 10 of resilient material is looselyl placed onto thatportion of bolt 6 which extends 'beyond the follower 9 of lever 7 and isheld in such po- .sition with slight freedom of axial movement by aretaining member or washer 11 which is maintained at the free `end ofbolt 6 by a slotted disk 11a radially slidable into a suitable reducedneck zone of the bolt (not shown). ASleeve 10 is axially slidable onmember 6 and, being of elastic nature in that it is made of rubber or alike substance, may be deformed by the follower 9 of lever 7 lwhen thelatter isturned about the bolt 6 and travels toward the raised portionsof cam surfaces 4. It will be noted that the cam surfaces 4 and stops 3are disposed adjacent to the periphery or mantle of resilient member 10and that the lower end face of said member rests upon the follower 3.

When the releasable mechanical connection is in open or non-retainingposition, all parts are in the position shown in full lines in Figs. 1and 2. The typewriter I. 12a, shown only in Fig. 1, is then placed ontothe structural element or base 1 in such manner that a portion of itsframe 12, which is provided with a bore or aperture 13,1surrounds aportion of the peripheral zone or mantle of resilient member 10 andrests upon the stops or abutments 3 of protuberance 2. By turning lever7 in the `direction of arrow A, follower 9 slides along the cam surfaces4 in upward direction away from the base or structural element 1 andcauses movement of resilient sleeve 10 in the axial direction of bolt 6upwardly toward the disk or washer 11. Upon further angular movement oflever 7 in the same direction, its follower 9 abuts against the adjacentend and causes compression of sleeve 10 in the axial direction of bolt 6whereby the sleeve defines an annular bead or bulge 10a which is shownin phantom lines in Fig. 1. When the follower 9 is turned through about180 degrees, a portion of sleeve or cylinder 10 extending beyond thatsurface ofrframe 12 Vwhich is turned away from base plate 1 iscompressed to such an extent that the bulge or bead 10a positivelyprevents removal of frame 12 over thefree end of bolt 6.

The removal of portable machine 12a with its frame or structural element12 is carried out by reversing the above-described sequence of steps.Thus, level 7 iS turned in a direction opposed to that indicated byarrow A whereby the follower 9 descends by sliding along sloping camsurfaces 4 in downward direction toward base 1 t0 permit expansion ofcylinder orsleeve 10 back into its full-line position. The bulge 10a`disappears as the upper end of sleeve 10 moves away from washer 11 andthe frame 12 may be removed over the free end of bolt 6.

It will be understood that the compression of cylinder or sleeve 10 neednot be such as to cause the formation of a bulge or bead 10a thereon, itbeing often suflicient that the cylinder 10 and frame 12 engage merelyby friction to anextent satisfactory to provide a connection ofreasonable strength between structural elements 1 and 12. It willfurther be understood that, when the improved releasable connection isutilized with a portable typewriter, at least two but preferably moresuch assemblies are installed on, or formed integrally with, the base 1,each assembly being operable by its own lever or actuating device 7. Asbefore stated, the connection has been shown as applied to the base of atypewriter case only by way of example since its field of application ispractically unlimited, the improved system being capable of use whenevera releasable connection between two structural elements is required.

In addition,'the compression of sleeve or cylinder 10 may be broughtabout by a modified lever 7 and by a modified cam assembly 3, 4. Forexample, the lever need not be swingable about bolt 6 but may beprovided with an elongated slot and so installed as to be slidable in adirection which is radial with respect to the axis of member 6. The camassembly 3, 4 then requires some modification insofar as it should causethe actuating device to descend in a direction toward the structuralelement to which the lower end of the bolt is fixed for release of theconnection, and should bring about compression of the resilient memberby the actuating device when the latter is in another radial positionfarther away from said structural element. In other words, the novelmechanical connection for releasably joining a stationary structuralelement with a removable structural element may be actuated by anydevice having a first position in which the resilient retaining memberor sleeve is compressed to retain, either frictionally or by theformation of a bulge, the removable structural element, and a secondposition in which the resilient member is free to assume its normalunstressed shape to permit disconnection of the removable structuralelement.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various .applications without omitting featuresthat, from the vstandpoint of prior art, fairly constitute essentialcharacteristics of the generic and specificaspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

We claim:

1. A mechanical connection for releasably joining a pair of structuralelements one of which has an aperture, said connection comprising, incombination: a supporting member having an axis, a first end connectedwith the other of said structural elements, and a free end; a camassembly defining at least one cam surface and connected with said otherstructural element; a retaining member connected with the free end ofsaid supporting member; a resilient member receiving said supportingmember and disposed between said retaining member and said cam assembly;and an actuating device mounted on said sup porting member intermediatesaid resilient member and said cam assembly for movement along the camsurface relative to said Supporting member between a first position inwhich said resilient member is in unstressed condition and a secondVposition in which said resilient member is compressed between saidactuating device and said retaining member and subjected to deformation,said connection operating in such manner that, when said resilientmember is inserted in unstressed condition into ient member engages withsaid one structural element and 3 connects same with said otherstructuralelementrand, when said actuating device is returned into saidiirst position the resilient member returns into'unstressedlconditionand may be withdrawn from the aperture in fsaid one structural element.

2. A mechanical connection comprising, in Vcombination: a structuralelement; a cam assembly connected with said structural element andhaving a pair of-cam surfaces sloping with respect to saidstructural'element; a-supporting member connectedwithlandextending fromsaid structural element intermediate said cam surfaces, 'and having afree end; a retaining member at Vthe free end of'saidsupporting member;a resilient sleeve von said supporting member, said sleeve having aiirst vend adjacent to said retaining member and a second endiadjacent'to said cam surfaces; and an actuating device comprising a followermounted on said supporting member interme- "diate the second end of saidsleeve and said wm surfaces in such '-manner as to havefreedom ofmovement with respect' to --said Vsupporting member along -said Acam*surfacesbetween'a first position-in which it compressesfand deformssaid sleeve by moving -the latteriagainst -said 'retaining member and aAsecond position in `which'said sleeve isin unstressed condition.

3. -A mechanicalconnection comprising, =in`combina tion: ya-structuralelement; a cam-assembly connected withsaid structuralelement andliavingapair of cam surfaces sloping with respect to -said structural-element;al supporting member having an'axis, connected -with and extending fromsaid structural elementintermediate said cam'surfaces, land havinga-free endya retaining member atthefree end of said supporting member; a-resilient sleeve' axially slidably mounted onfsaidsupporting-member,'said-sleeve having Va `first end adjacentto 'saidVretaining-member and a'isecond end adjacent to'said-'camsurfaces; and anactuating device comprising -a follower vmounted `on-said supportinglmember intermediate the see'cond yend of said sleeve and saidcamtsurfaces in'such Inanner as-to havefreedom ofmovementwithrespect tosaid supporting member along'said' camsurfacesl'between aiirst'positionin/which it compresses and deforrnsfsaid 'sleevcbymoving thelatteragainst said-retaining. member AVand a second position in which saidlsleeveis in'unstressed "condition "4. A mechanicd connection comprising,'in combination: a structural element; a substantially 4annular camassembly "connected with said structural element-and having'a pair ofsubstantially semicircular cam 'surfaces slopingyvith`-re-spect tosaid'structural element; a supporting member'connected withandextending'from said struc- 'turalelement intermediate saidcamsurfaces, and having afree end; a retaining member at thefree end ofvsaid supporting member; a resilient sleeve onsaid supporting member,said sleeve having a first end adjacentto lsaid 'retaining member and asecond end adjacent to said cam surfaces; and anactuating'devicecomprising a follower rotatably -mounted on said supporting memberinter- 'mediatethe second end of said sleeve and saidcam'surfacesin suchmanner as to have freedom of angular movelment with respect to saidsupporting member alongsaid cam surfaces between a first position inwhich it compresses vand deforms said sleeve by moving the `Ilatter'against said retaining member and a second position in whichsaidsleeveis in unstressed condition.

5. A mechanical connection comprising, in-combinationastructuralelement; a cam assembly connected with "said structural element andhaving a'pair of spaced cam surfaces sloping with respect'to saidstructural element; a supporting member having an axis, connected withand extending from said structural element intermediate said camsurfaces, and having a free end; aretaining member 'at the free `end ofsaid supporting member; Va resilient sleeve 'on said supportingmember,said'sleevehavin'ga rst'end adjacent to'said'retaining member and asecond *end adjacent to said cam surfaces; and an actuating* devicefcomprisingia"followermounted'forradialmovernents with respectrto 'theaxis :of saidesupporting'member intermedi- -atethe vsecond end of saidsleeve and said camsurfaces 'alongsaid camsur'faces between aiirst'radial position in which it compresses and deforms said sleeve bymov- `ing thelatteria'gainst said retaining member and a secondradialposition in which said sleeve is in unstressedcondition.

16. A mechanical "connection comprising, incombination:aistructuralelemenn a'cam assembly integral with said.structural element and having a' pair of cam surfaces Asloping withrespect to-said structural clement; a supporting member connected withand extending-from Asaid structuralelement intermediate said camsurfaces, and havinga free end; a'retaining member atthe yfreelend Aofsaid'supportingmember; a resilient lsleeve on said supportingmember,.said .sleeve having a rst end lacl.- jacent 'to .said retaining 'memberand 'a second end `adjacentzto said cam surfaces; and an actuatingdevice comprising a follower mounted on said supporting member.intermediateithe second endfof said sleeve and said cam:surfaces-in'such:mannertastohave freedom of movement withfrespectto'said-supporting member along'saidy cam surfaces between a rstposition in which 'itcompresses .andrdeforms said sleevelby movingthelatter against said tretaining fmemberianda ysecond position'in whichsaid sleeveis in unstressed 'condition 7. vA mechanical connection 1comprising, `rin combination: a plate; la cam assembly integralwith saidvplate and "having a ,pair of :cam `.surfaces sloping with :respecttotheplane of said plate; a bolt connected with and extending from-saidplate'intermediate sai`d= cam surfaces,'andhaving afreezendidistant from said plate; fa

retaining-washeratthe freeendofsaidbolt; a resilient cylinder Aon saidbolthaving a rst end adjacentvto :said -washer anda second enda'djacentto said cam surfaces; andzan actuating lever comprising alhandgripportion distant from saidbolt 'and a'follower portion mounted onsaid,bolt'intermediatethesecondend of said'cylinder andffsaid camsurfaces inisuchmanner as to have'freedom of movement withrespect to`vsaidboltalong said cam surfaces between arst position inwhich'itcompresses and yatleast slightly'deforms said-cylinder by movingthe latteragainst'saidwasher and a `second positionin which-saidcylinder is'in unstressed condition. i

y'8. Am'echanical connection comprising, incombination: v-aplateya'substantially annular cam Vassembly integral withsaidplate andhaving apair of substantially semicircular cam surfaces sloping withrespect to f'the 'plane of:said2plate and azpairlofidiametricallyopposed stop members; :a bolt connected with andeXtending from .saidplate intermediate said cam surfaces., and having :a

free `enddistant'from'.said plate; a retaining'washer at the. free :endof said bolt;ia. resilient cylinderon said bolt havingfarst end adjacentto'said washer and-a second end adjacent to said cam surfaces; and-anactuating lever comprising handgrip portion distant fromsaidbolt andafollowerportion rotatably mounted on said bolt intermediate the secondend of said cylinder and said cam surfaces in such manner'asto havefreedom'of angular movement with respect to saidfbolt along said camsurfaces and intermediate said stop membersbetween a rst angularposition in which it-compresses and -at least slightly deformssaid-cylinder by. moving thelatter against said washer anda secondangular position :in which said cylinder is in unstressed condition.

59. In combination: :anbase plate having aniupper side; a projectionintegral with said-.base plate and extending above `said upper side,saidprojection defining a pair iof spaced cam surfaces-inclined withrespect to said upper side; albolt connected with'said base plate,extending upwardly between said cam surfacesfand having a -free .endspaced from said upper'side; a retainingimemberiixed'to the freecndofsaid-bolt;fa resilientfcylinder'loosely 'receive'dfon said boltintermediate fsaid-cam'surfaces--and said retaining member, saidcylinder having an upper end, a lower end and a peripheral zone; anactuating lever having a follower portion mounted on said boltintermediate the lower end of said cylinder and said cam surfaces insuch manner as to have freedom of movement with respect to said bolt andalong said cam surfaces between a first position in which it compressesand deforms said cylinder by moving the latter in upward directionwhereby the upper end of said cylinder abuts against said retainingmember, and a second position in which said cylinder is in unstressedcondition; and a typewriter having a frame dening an aperture of adiameter slightly exceeding the diameter of said cylinder when thelatter is in unstressed condition whereby, when said frame is placedonto said base in such manner that the peripheral zone of said cylinderextends into and through said aperture and said follower portion ismoved Vmember fixed to the free end of said bolt; a resilient cylinderloosely received on said bolt intermediate said cam surfaces and saidretaining member, said cylinder having an upper end, a lower end and aperipheral zone;

Yan actuating lever having a follower portion mounted on said boltintermediate the lower end of said cylinder Vand said cam surfaces insuch manner as to have freedom of movement with respect to said bolt andalong said cam surfaces between a first position in which it compressesand deforms said cylinder by moving the latter in upward directionwhereby the upper end of said cylinder abuts against said retainingmember, and a second position in which said cylinder is in unstressedcondition; and a typewriter having a frame defining an aperture of adiameter slightly exceeding the diameter of said cylinder when thelatter is in unstressed condition whereby, when said frame is placedonto saidv base in such manner that the peripheral zone of said cylinderrextends into and through said aperture and said follower portion ismoved into said first position, the cylinder is deformed and engagessaid frame to connect the type- .writer with said base plate.

ll. In combination: a base plate having an upper side; a projectionintegral with said base plate and extending above said upper side, saidprojection defining a cam assembly consisting of a pair of substantiallysemicircular cam surfaces inclined with respect to said upper side and apair of diametrically opposed stop members intermediate said camsurfaces; a bolt connected with said base plate, extending centrallyupwardly between said cam surfaces and having a free end spaced fromsaid upper side; a retaining member fixed to the free end of said bolt;a resilient cylinder loosely received on said bolt intermediate saidprojection and said retaining member, said cylinder having an upper end,a lower end and a peripheral zone; an actuating lever having a followerportion rotatably mounted on said bolt intermediate the lower end ofsaid cylinder and said projection in such manner as to have freedom ofangular movement with respect to said bolt intermediate said stopmembers and along said cam surfaces between a first position in which itcompresses and deforms said cylinder by moving the latter in upwarddirection whereby the upper end of said cylinder abuts against saidretaining member, and a second position in which said cylinder is inunstressed condition; and a typewriter having a frame defining anaperture of a diameter slightly exceeding the ,diameter of saidcylinder` when the latter is in unstressed condition whereby, when saidframe is placed onto said base in such manner that the peripheral zoneof said cylinder extends into and through said aperture and saidfollower portion is rotated into said first position, the cylinder isdeformed and engages said frame to connect theV typewriter with saidbase plate.

l2. In combination: a base plate having an upper side; a projectionintegral with said base plate and extending above said upper side, saidprojection defining a pair of spaced cam surfaces inclined with respectto said upper side; a bolt connected with said base plate, extendingupwardly between said cam surfaces and having a free end spaced fromsaid upper side; a retaining member fixed to the free end of said bolt;a resilient cylinder loosely received on said bolt intermediate said camsurfaces and said retaining member, said cylinder having an upper end, alower end and a peripheral zone; an actuating lever having a handgripportion distant from said bolt and a follower portion mounted on saidbolt intermediate the lower end of said cylinder and said cam surfacesin such manner as to have freedom of movement with respect to said boltand along said cam surfaces between a first position in which itcompresses and deforms said cylinder by moving the latter in upwarddirection whereby the upper end of said cylinder abuts against saidretaining member, and a second position in which said cylinder is inunstressed condition; and a typewriter having a frame defining anaperture of a diameter slightly exceeding the diameter of said cylinderwhen the latter is in unstressed condition whereby, when said frame isplaced onto said base in such manner that the peripheral zone of saidcylinder extends into and through said aperture and said followerportion is moved into said first position, the cylinder is deformed andengages said frame to connect the typewriter with said base plate.

13. In combination: a base plate having an upper side; a projectionintegral with said base plate and extending above said upper side, saidprojection defining a pair of spaced cam surfaces inclined with respectto said upper side; a bolt connected with said base plate, extendingupwardly between said cam surfaces and having an axis and a free endspaced from said upper side; a retaining member fixed to the free end ofsaid bolt; a resilient cylinder axially slidably received on said boltintermediate said cam surfaces and said retaining member, said cylinderhaving an upper end, a lower end and a peripheral zone; an actuatinglever having a follower portion mounted on said bolt intermediate thelower end of said cylinder and said cam surfaces in such manner as tohave freedom of movement with respect to said bolt and along said camsurfaces between a first position in which it compresses and deformssaid cylinder by moving the latter in upward direction whereby the upperend of said cylinder abuts against said retaining member, and a secondposition in which said cylinder is in unstressed condition; and atypewriter having a frame defining an aperture of a diameter slightlyexceeding the diameter of said cylinder when the latter is in unstressedcondition whereby, when said frame is placed onto said base in suchmanner that the peripheral zone of said cylinder extends into andthrough said aperture and said follower portion is moved into said firstposition, the cylinder is deformed and engages said frame to connect thetypewriter with said base plate. y

14. A mechanical connection for releasably joining a pair of structuralelements one of which has an aperture, said connection comprising, incombination: a supporting member having an axis, a first end connectedwith the other of said structural elements, and a free end; a'

of said supporting member; a resilient member receiving said supportingmember and disposed between said retaining member and said cam assembly;and an actuating device mounted on said supporting member intermediatesaid resilient member and said cam assembly for movement along said camsurfaces relative tosaid supporting member between `a rst position inwhich said resilient member is in unstressed condition Iand a secondposition in which said resilent member is compressed between saidactuating device and said retaining member and subjected to deformation,said connection operating in such manner that, when said resilientmember is inserted in unstressed condition into the aperture in said onestructural element and said actuating device is moved into said secondposition, the resilient member engages with said one structural elementand connects same with said other structural element and, when saidactuating device is returned into said rst position the resilient memberreturns into unstressed condition and may be withdrawn from the aperturein said one structural element.

15. A mechanical connection for releasably joining a pair of structuralelements one of which has an aperture, said connection comprising, incombination: a cam assembly integral with the other of said structuralelements and dening a pair of substantially semicircular cam surfacessloping with respect to said other structural element; a supportingmember having an axis, a first end connected with said other structuralelement, extending from said other structural element substantiallycentrally between said cam surfaces, and having a free end distant fromsaid other structural element; a retaining member at the free end ofsaid supporting member; a resilient cylinder receiving said supportingmember and disposed between said retaining member and said otherstructural element; and an actuating device rotatably mounted on saidsupporting member intermediate said cylinder and said cam assembly forangular movements along said cam surfaces and about said supportingmember between a first position in which said cylinder is in unstressedcondition and a second position in which said cylinder is compressedbetween said actuating device and said retaining member and subjected todeformation, said connection operating in such manner that, when saidcylinder is in unstressed condition and is inserted into said apertureand said actuating device is rotated into said second position, thecylinder engages with said one structural element and connects same withsaid other structural element Whereas, when said actuating device isrotated back into said rst position the cylinder returns into4unstressed condition and may be withdrawn from said aperture.

No references cited.

